// Extend.js (http://code.google.com/p/extendjs/)
// Copyright 2010 Shumpei Shiraishi All rights reserved.
// Licensed under the MIT license.

(function(_global) {
    // undefined
    X.extend("Undefined", function(value) {
	return value === undefined;
    });
    X.Undefined.extend({
	isUndefined: function() {
	    return true;
	},
	isEmpty: function() {
	    return true;
	},
	toString: function() {
	    return "undefined";
	}
    }, true);

})(this);
